Mosquito-borne infectious diseases continue to plague mankind. These diseases have significant impact on the health and economy of much of the world. Alternative strategies for control of mosquito vectors could arise through a greater understanding of the genetics and physiology of these insects. Progress in genetic research with mosquitoes would be greatly enhanced by the development of an effective means of transgenic manipulation of mosquitoes. A key component of this capability would be the identification of insect transposons that are able to efficiently vector a gene into the mosquito genome and maintain it in an active state. The insect transposon piggyBac has proven effective for genetic manipulation in widely diverse lepidopteran species. We have also shown that this transposon is capable of transient movement in microinjected mosquito embryos. This proposal seeks short-term funding for a pilot study to explore the potential capabilities of this transposon for establishing transgenic strains of the mosquito species, Aedes aegypti. A piggyBac element carrying a selectable insecticide resistance gene, hsp/opd, that has already proven effective for establishing transgenic insect strains, will be introduced by microinjection into Ae. aegypti embryos. The presence of the transposon will be detected following paraoxon selection at the G1 generation using Southern hybridization, and PCR amplification, cloning, and sequencing. Further analyses of the stability and movement of transposon sequences within the mosquito genome will be undertaken as time and progress permits. This research will expand this laboratory's capabilities for exploring transgenesis in mosquitoes, and if successful, will provide an exciting and much needed capability for significant enhancement of the basic research effort in mosquito genetics and physiology.